﻿using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Net;
using System.Net.Sockets;
using System.Threading;
using ProtocoloCarSharing;

namespace ServidorCommunications
{
   // State object for reading client data asynchronously
    public class StateObject {
        // Client  socket.
        public Socket workSocket = null;
        // Size of receive buffer.
        public const int BufferSize = 1024;
        // Receive buffer.
        public byte[] buffer = new byte[BufferSize];
    // Received data string.
        public StringBuilder sb = new StringBuilder();  
    }

    public class ConexionSockets
    {
        // Thread signal.
        public static ManualResetEvent allDone = new ManualResetEvent(false);
        private IPAddress _ipServidor;
        private int _puertoTCP;

        public ConexionSockets(IPAddress ipServidor, int puertoTcp)
        {
            _ipServidor = ipServidor;
            _puertoTCP = puertoTcp;
        }

        public void StartListening()
        {
            // Data buffer for incoming data.
            byte[] bytes = new Byte[1024];

            IPEndPoint localEndPoint = new IPEndPoint(_ipServidor, _puertoTCP);

            // Create a TCP/IP socket.
            Socket listener = new Socket(AddressFamily.InterNetwork,
                SocketType.Stream, ProtocolType.Tcp);

            // Bind the socket to the local endpoint and listen for incoming connections.
            try
            {
                listener.Bind(localEndPoint);
                listener.Listen(100);
                Console.WriteLine("Esperando por una conexion...");

                while (true)
                {
                    // Set the event to nonsignaled state.
                    allDone.Reset();

                    // Start an asynchronous socket to listen for connections.                 
                    listener.BeginAccept(
                        new AsyncCallback(AcceptCallback),
                        listener);

                    // Wait until a connection is made before continuing.
                    allDone.WaitOne();
                }

            }
            catch (Exception e)
            {
                Console.WriteLine(e.ToString());
            }

            Console.WriteLine("\nPresiona la tecla enter para continuar...");
            Console.Read();

        }

        public static void AcceptCallback(IAsyncResult ar)
        {
            // Signal the main thread to continue.
            allDone.Set();

            // Get the socket that handles the client request.
            Socket listener = (Socket)ar.AsyncState;
            Socket handler = listener.EndAccept(ar);

            // Create the state object.
            StateObject state = new StateObject();
            state.workSocket = handler;
            handler.BeginReceive(state.buffer, 0, StateObject.BufferSize, 0,
                new AsyncCallback(ReadCallback), state);
        }

        //Aca empiezo a recibir el mensaje
        public static void ReadCallback(IAsyncResult ar)
        {
            String content = String.Empty;

            // Retrieve the state object and the handler socket
            // from the asynchronous state object.
            StateObject state = (StateObject)ar.AsyncState;
            Socket handler = state.workSocket;

            // Read data from the client socket. 
            int bytesRead = handler.EndReceive(ar);

            if (bytesRead > 0)
            {
                // There  might be more data, so store the data received so far.
                state.sb.Append(Encoding.ASCII.GetString(
                    state.buffer, 0, bytesRead));

                // Check for end-of-file tag. If it is not there, read 
                // more data.
                content = state.sb.ToString();
                if (content.IndexOf(Protocolo.END_OF_MSJ) > -1)
                {
                    //Aca tengo que administrar los mensajes y mandar uno nuevo
                    Console.WriteLine(content + "\n");
                    byte[] mensajeBytes = Encoding.ASCII.GetBytes(content);
                    MensajeProtocolo msjProtocolo = new MensajeProtocolo(mensajeBytes);

                    AgenteVehiculoManager manager = new AgenteVehiculoManager();
                    MensajeProtocolo response = manager.ManageMensajesAgenteVehiculo(msjProtocolo);
                    
                    //Mando el mensaje formado
                    Send(handler, response);
                }
                else
                {
                    // Not all data received. Get more.
                    handler.BeginReceive(state.buffer, 0, StateObject.BufferSize, 0,
                    new AsyncCallback(ReadCallback), state);
                }
            }
        }

        //Aca respondo el mensaje
        private static void Send(Socket handler, MensajeProtocolo response)
        {
            // Convert the string data to byte data using ASCII encoding.
            byte[] byteData = response.ConvertirAByte();

            // Begin sending the data to the remote device.
            handler.BeginSend(byteData, 0, byteData.Length, 0,
                new AsyncCallback(SendCallback), handler);
        }

        private static void SendCallback(IAsyncResult ar)
        {
            try
            {
                // Retrieve the socket from the state object.
                Socket handler = (Socket)ar.AsyncState;

                // Complete sending the data to the remote device.
                int bytesSent = handler.EndSend(ar);
                //Console.WriteLine("Sent {0} bytes to client.", bytesSent);

                handler.Shutdown(SocketShutdown.Both);
                handler.Close();

            }
            catch (Exception e)
            {
                Console.WriteLine(e.ToString());
            }
        }        
    }
}
